There are several ways one person can reach another person, such as, for example, fax machines, cellular telephones, pagers, electronic mail, and voice mail. Although an individual's telephone number may be found utilizing directory assistance or a telephone directory, there is no convenient way to find the other numbers or addresses for many of these new forms of communication.
It has recently become possible to retrieve names and physical addresses of individuals based on the telephone number associated with the individual. This is commonly referred to as Reverse Directory Assistance (or, Reverse DA) and is implemented in existing switch-based telecommunications systems. However, it is desirable to retrieve the other addresses associated with the individual based on the individual's known telephone number.